The present invention is directed to medical and laboratory fluid specimen collecting and testing apparatus, and more specifically to an apparatus for testing for the presence of specific antigens in biological fluids.
The family of immunoassay works upon the simple principle that is the specific recognition of an antigen by an antibody. Thus specific antigen detection and quantification requires an antibody which recognizes the uniqueness of an antigen. The antigen binding site of antibodies recognizes about six amino acids or their equivalent in mass. One unique binding site serves as an identifying marker for that protein.
When a definitive antibody for a given antigen is available it is used to identify the antigen in the sample mixture. Once the antibody combines with the antigen a means is needed to recognize the complex. There presently exists a need to concentrate antigens from volumes of fluid when the antigen is not present in measurable quantities in specific fluid volumes.
The present invention is directed toward a method which can use immunoassay in sample treatment apparatus for diagnostic and testing purposes of specific urine antigen by concentrating the specific urine antigen by capturing it with an immobilized antibody on a bead in a small volume area, washing the antigen-antibody complex, engaging the antigen-antibody complex with a solution of prelabelled primary antibody so that the captured antigen bonds with the prelabelled primary antibody as a sandwich complex and mixing the antigen-antibody sandwich complex with a coloring reagent to obtain a test color.
It is generally necessary in diagnosing and testing for many diseases to collect biological fluids from a patient, e.g., sputum, blood, pleural and peritoneal cavity fluids, urine, etc. for analysis. It is important during the collection handling of biological fluid specimens that the potential of specimen contamination and the spread of any infection from the specimen be minimized. While urine is commonly collected in 100 ml containers the actual urine testing is commonly conducted with relatively small amounts of sample around 0.2-0.5 ml in volume. Thus because of the small test quantity, cancer producing antigen can only be ascertained after the cancer is in an advanced or late tumor stage. The rest of the urine sample is used for further testing or is thrown away. Additional problems occur in shipment when dealing with urine because of the relatively large volume of fluid involved in the collection specimen sample. There is also the risk of sample deterioration because of the relatively short sample shelf life of urine unless kept in specific temperature conditions. In addition there is also the potential for specimen damage or spillage during the collection and/or shipment process as well as the potential for destruction of certain molecular components of the specimen such as antigens contained therein, because the packaging does not protect the urine or causes chemical changes of different fluid components which will negate the test results or result in false data being obtained when the specimen is tested.
There currently exists a need to provide a test procedure to test for molecular components of biological fluids for the presence of cancer at an early stage in the development of the cancer.
A typical specimen collecting apparatus is shown by U.S. Pat. No. 4,741,346. This apparatus includes a base stand which supports the specimen vial in an upright position. A funnel is inserted in the open end of the specimen vial and surrounds and encloses the upper portion of the vial. The base stand has an upwardly extending tubular wall which at least partially surrounds the vial in connection with the cap and allows the user to remove the vial without touching the surface or coming in contact with the specimen. Examples of various types of liquid containers for collecting and transporting urine are shown by U.S. Pat. Nos. 3,777,739; 3,881,465; 4,042,337; 4,084,937; 4,244,920; 4,492,258 and 4,700,714.
Another specimen collection device shown by U.S. Pat. No. 4,040,791 discloses a collection receptacle having a nipple upon which is mounted a specimen container which receives a predetermined amount of the specimen in a sealed condition. The specimen container is provided with an integally formed cap which is placed over the opening in which the collector nipple is inserted. U.S. Pat. No. 4,557,274 discloses a midstream urine collector having a funnel which transmits urine into a cup member which is covered by a membrane cover.
A combined strip testing device and collection apparatus is shown by U.S. Pat. No. 4,473,530 and is directed to an apparatus which integrates testing and collection by having chemical reagent test strips present within the tube together with specific gravity reading means allowing immediate testing of the urine. U.S. Pat. No. 4,573,983 is directed towards a liquid collection system having an antiseptic member on the discharge section which uses a filter of air and bacteria impervious material to filter the urine.
It is therefore desirable to provide an easy to handle method for allowing more sensitive cancer detection from the sample while also providing that the test specimen can be compactly stored for a period of time in concentrated form allowing cancer testing to be performed quickly and accurately by distal testing facilities with minimum elapse of time.